Apparatus for cleaning filters.



vv. F. L. BETH.

APPARATUS FOR CLEANING FILTERS.

APPLICATION FILED DEC I, 1911.

PatentedSept. 14, 1915.

III I I l G II IIIIEI I IIII WILHELM FRIEDRICH LUDWIG BETH, LBECK, G-Erlw ,a

yAEIAIRA'ILU'S FOR CLEANING FILTERS.

Specification o f Letters Patent.

Patenten sept. it, reis..

Application led December 1,1911. Serial No. 663,313.

To aZZ 'whoin t may concern `Be it known that I, WILHELM FRIEDRICHLUDWIG BETH, manufacturer, subject of the German Emperor, residing atLbeck, Germany, have lnvented certain new and useful Improvements in"Apparatus for Cleaning Filters, of which the following is aspecification.

My invention relatesl to improvements in apparatus for cleaning filtersby shaking the same, and the object of the improvements is to provide anapparatus in which the movable parts of the operating'fmechanism are notsubjected to the shocks caused by the shaking operation, which shockscause a rapid wear ofthe said movable parts.

With this object in view my invention consists in providing an apparatusfor shaking the filters in which the shaking member is actuated from theoperating gearing, through the intermediary of a force which is devoidof positive transmission connections with that member. This shakingmember is preferably constituted by the reciprocating piston of a motorwhich is adapted to be operated by a suitable fluid under pressure orunder a vacuum, and which is controlled by a rotating driving gear andtransmits its reciprocating movement directly to the filters.

Filters for dust-laden air have been proposed, (see for example,applicants prior German Patents, Nos.- 52,812, 105,489, 164,001 and169,361), in which the cleaning of the filters is effected through theagency of vibrating tapping fingers and similar devices thatperiodically strike the levers bearing the filters, whereby the latterare vehemently shaken. These cleaning devices, especially when appliedto large or heavy filters, are open to serious defects, in that theaforesaid tapping fingers and levers are subjected to considerable wearand tear, and the former set up in the belts, gearing, or other drivingmechanism recoils of comparatively reat ,intensity which are manifestlyinjurious thereto and which are transmitted in the form of intenseshocks to the adjacent parts of the building; also, such devices, whenin action, are extremely noisy. The objectionable featuresaforementioned are completely avoided by the improved constructionhereinabove briefiy described, the piston member of the Huid-actuatedmotor comprehended in this construction having -no intermediate gear orother mechanical connections with the driving mechanism.

lin order that my invention may more clearly be understood, a structuralembodi- -ment thereof is illustrated in the accompanying drawing whichshows a vertical section of the filtering apparatus and the apparatusfor shaking the lters.

Referring to the drawing, a suitable number of filters e of any known orpreferred construction are suspended from a rod y within a filteringchamber m. At their lower ends the filters are secured to the bottom m1of the filtering chamber, and through apertures m2 the filters open intoa funnel ZJ through which the dust deposited on the inner surfaces ofthe filters can be removed. The said funnel is provided with an inletstud g, through which the dust-laden air is admitted to the filters. Atits top the filter chamber m communicates with valve-controlled suctionmeans, preferably consisting of a valve chamber s1 which at one side isconnected by a pipe g to an exhaust fan, (not shown), said chambercontaining a hinged Hap valve s. At its opposite side the valve chamberhas an opening through which pure air, preferably underpressure, can beadmitted to the filter chamber when shaking the filters. Theaforementioned flap valve c is adapted to be rocked into one of twopositions indicated in full and dotted lines, whereby the filteringchamber is connected either to the passage g and to the eX- haust fan,or to the inlet o for pure air under pressure. As shown the rod 1/ isconnected to a reciprocating member such for example as thereciprocatory pistoni of a motor whose casin or cylinder Z is secured onthe top of the ltering chamber.- ln the present construction a solidconnection is shown between the reciprocating piston and the filters z,but I wish it to be understood, that my invention is notlimited to suchconstruction. A suitable motive fiuid, such as compressed air, isadmitted to the cylinder Z through a conduit n, and the piston isreversed after each stroke by any known or preferred means. In theexample shown a drag cylinder 7c is used for this purpose which slideswithin the cylinder Z and is taken along by the piston 7c during itsstroke in` either direction. The cylinders Z and Za are provided withinlet and outlet ports Z1, cl and Z2, 7:2, and corresponding inlet andwas outlet ports are adapted to be brought -in register by thereciprocation of the cylinder la. Thereby the motive fluid supply andthe exhaust port Z2 are alternately connected to or disconnected fromthe cylinder Z and the piston z', so that reciprocating movement isimparted to the latter.

The supply of motive fluid to the motor is automatically controlled, andthe' said controlling means is operatively connected With the hingedvalve s in such a Way that the eX- haust fan is shut off from thefiltering chamber and thereby the supply of impure air thereto isstopped When shaking takes place.

In the example shown, the controlling means consists of a springactuated piston valve it Which is operatively connected with the hingedvalve s by means of a rocking lever f and a connecting rod f1. In theposition of the parts shown in full lines, the motive fluid supply tothe motor is opened, and the valve s connects the filter chamber to theatmosphere or to a supply of pure air under pressure and closes itagainst the exhaust fan. Therefore the exhaust fan is cut out ofoperation and the filters are being shaken by means of the piston z'. Ifthe valve h and the hinged valve s are shifted tothe right andA intotheposition shown in dotted lines, the admission of the motive fiuid tothe motor is closed, thus cutting the latter out of operation and theexhaust fan is connected to the filter chamber. Therefore, the shakingof the filters is stopped, and impure air flows again to the filterchamber.

In the preferred form, the operation of the valve s and the valve zy isautomatically controlled at suitable periods. As shown, the operatingmeans consist of a slowly rotating cam a; Which once for each rotationlifts a rod f2, connected to the lever f, into b position for engagementby a rather rapidly rotating cam d. The said cams are mounted on asuitable bracket t. The cam d is rotated by means of a pulley Z1 and abelt trained thereon, and the cam a is rotated by means of asv-crm geara2, a1. -At its rear the rod f2 is forked and each of its branches .f isformed with a nose 1" and e'respectively.

XVhen the rodi;c2 is lifted by the cam a the lower nose cis in positionfor engagement by the cam d, so that the rod f1, the valve h and theflap s are shifted into the position shown in full lines in Whichshaking takes place. As the cam a gradually proceeds the rod f2 dropsdownward, with its nose e out of engagement with the cam Z and with itsnose 1 into position for engagement there- With, so that the valve h andthe fiap s are shifted to the right and the cylinder l is shut ofiI fromthe pressure fluid supply.

Though in Adescribing the linvention reference has been made to aconstruction, in which the rocking valve s is directly operated by thegear of the valve lz., I Wish it to be understood, that my invention isnot limited to the construction shown, and that other means may beprovided to move the valve s, such for example as a special motor, anelectromagnet, or the like.

I claim herein as my invention:

1. In filter cleaning apparatus of the character described,thercombination with a' filter supporting member, of a reciprocablemotor having a free piston that is directly connected to the filtersupporting member and operative to alternately distend and relieve suchdistension of the filters, and automatic controlling means for causingreciprocation of said motor at predetermined intervals.

2. In filter cleaning apparatus of the character described, thecombination with a filter supporting member, and means for alternatelysubmitting the filter chamber to the action of compressed air and avacuum, of a Huid-actuated motor having a free piston that is connectedto the filter' supporting member and operative to raise and lower thesame to alternately tension and relieve such tension on the filters, anda controller operative to automatically time the operations of saidmotor and said compressed air and vacuum controlling means. y

3. In filter cleaning apparatus of the character described, thecombination with a filter supporting member, and valve means foralternately submitting the filter chamber to the action of compressedair and vacuum, of a fluid-actuated motor having a free pis- 100 tonthat is connected t0 said filter supporting member, and automaticcontrolling means common to said motor and valve, means for causing themotor at timed intervals to distend the filters While the filter 105chamber is subjected to the action of compressed air and to cause themotor to relieve such distention of the filters While the filter chamberis subjected to vacuum action.

4. In filter cleaning apparatus of the 110 character described, thecombination with a yfilter supporting member, and means for alternatelysubjecting the filter chamber to compressed air pressure and vacuum, ofa reciprocable motor having a free piston that is directly connected tosaid filter supporting member, and an automatic controller operative tocause reciprocation of the motor in one direction While the filterchamber is subjected to the action of compressed air 120,

ing member arranged to engage said projections alternately to shift saidrod endwise in opposite directions.

6,. ln an apparatus of the character specified, the'combination of afluid-actuated element, means for supplying motive fluid thereto, and acontroller for regulating the fluid supply comprising a valve, a rodconnected with the valve and having a forked end the branches of Whichare formed With a pair of opposed projections, and a rotary drivingmember disposed between said branches and arranged to engage saidprojections alternately to shift said rod endwise in oppositedirections.

7. ln an apparatus of the character speci'- ed, the combination of afluid-actuated element, means for supplying motive fluid thereto, and acontroller for regulating the uid supply comprising a valve, a rodconnected With the valve and having a pair of opposed projections, arotary driving member, and means for periodically rocking said rod tobring said projections alternately into position for engagement by saiddriving member.

8. ln an apparatus of the character specified, the combination of aHuid-actuated element, means for supplying motive uid thereto, and acontroller for regulating the fluid supply comprising a valve, a rodconnected with the valve and having a pair of opposed projections, arotary driving member, and a slowly-rotating cam operative upon said rodto rock the same periodically and bring Vsaid projections alternatelyinto position for engagement by said driving member.

ln testimony whereof I have hereunto set my hand in presence of twosubscribing Witnesses.

WILHELM FRIEDRICH LDWIG BETH.

Witnesses g Joint WULF, HERMANN RHODE.

